U.S. patent application number 12/879168 was filed with the patent office on 2011-03-10 for motor vehicle with a ride level control device.
This patent application is currently assigned to DR. ING. H.C. F. PORSCHE AKTIENGESELLSCHAFT. Invention is credited to Markus Atz, Thomas Hieber, Frank Poppe, Achim Schulz.
Application Number | 20110060502 12/879168 |
Document ID | / |
Family ID | 43603459 |
Filed Date | 2011-03-10 |
United States Patent
Application |
20110060502 |
Kind Code |
A1 |
Atz; Markus ; et
al. |
March 10, 2011 |
MOTOR VEHICLE WITH A RIDE LEVEL CONTROL DEVICE
Abstract
A motor vehicle is proposed having a ride level control device
with a pneumatic lift system , with a ride level control unit, to
which the operating parameters of the motor vehicle which are
detected by sensors are fed. The ride level control unit is active
if the ignition of the motor vehicle is switched on. Furthermore,
when various conditions are met, the ride level control unit
outputs a signal to the lift system so that the motor vehicle is
raised. A bidirectional connection is present between the ride
level control unit and the lift system in order to transmit
feedback from the lift system to the ride level control unit.
Inventors: |
Atz; Markus; (Weingarten,
DE) ; Hieber; Thomas; (Boertlingen, DE) ;
Schulz; Achim; (Niefern-Oeschelbronn, DE) ; Poppe;
Frank; (Kirchheim-Teck, DE) |
Assignee: |
DR. ING. H.C. F. PORSCHE
AKTIENGESELLSCHAFT
Stuttgart
DE
|
Family ID: |
43603459 |
Appl. No.: |
12/879168 |
Filed: |
September 10, 2010 |
Current U.S.
Class: |
701/37 |
Current CPC
Class: |
B60G 2600/044 20130101;
B60G 2400/823 20130101; B60G 2400/252 20130101; B60G 2600/18
20130101; B60G 2500/30 20130101; B60G 17/0155 20130101; B60G
17/0195 20130101; B60G 17/0165 20130101; B60G 2500/02 20130101;
B60G 2202/412 20130101; B60G 2800/914 20130101; B60G 2600/08
20130101; B60G 2400/382 20130101; B60G 2400/51222 20130101; B60G
2400/71 20130101; B60G 2600/20 20130101; B60G 17/018 20130101; B60G
2400/204 20130101 |
Class at
Publication: |
701/37 |
International
Class: |
B60G 17/016 20060101
B60G017/016; B60Q 1/06 20060101 B60Q001/06 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 10, 2009 |
DE |
10 2009 042 165.3 |
Claims
1. A motor vehicle, comprising: an ignition; sensors; and a ride
level control device having a pneumatic lift system and a ride
level control unit to which operating parameters of the motor
vehicle detected by said sensors are fed, said ride level control
unit being active if said ignition of the motor vehicle is switched
on, wherein when various conditions are met, said ride level
control unit outputs a signal to said lift system and lifting of
the motor vehicle takes place, wherein a bidirectional connection
between said ride level control unit and said lift system is
present and feedback from said lift system to said ride level
control unit takes place.
2. The motor vehicle according to claim 1, wherein a pressure in
said pneumatic lift system is measured, and in that the lifting up
of the motor vehicle is prevented if the pressure in said pneumatic
lift system is not sufficient or if a speed of the motor vehicle
exceeds a predefinable limiting value.
3. The motor vehicle according to claim 2, wherein the predefinable
speed is 60 km/h.
4. The motor vehicle according to claim 2, further comprising a
compressor, when the pressure in said lift system drops below a
lower predefinable value, said compressor is activated, and is
switched off again when an upper predefinable pressure is
reached.
5. The motor vehicle according to claim 4, wherein when said
compressor is activated after a defined time, the pressure is
checked again, and a fault message is issued when the pressure is
not reached.
6. The motor vehicle according to claim 1, further comprising: a
headlight; and a beam width adjuster connected to ride level
control unit, said beam width adjuster causes said headlight to be
lowered when the motor vehicle is raised.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority, under 35 U.S.C.
.sctn.119, of German application DE 10 2009 042 165.3, filed Sep.
10, 2009; the prior application is herewith incorporated by
reference in its entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The invention is based on a motor vehicle with a ride level
control device, wherein the bodywork of the vehicle can be placed
at a raised level with respect to the roadway in order to avoid
damage when the ground is uneven, and can be placed at a lowered
level.
[0003] Such an arrangement is known, for example, from German
patent DE 100 53 316 B4. In this known arrangement, a vehicle
bodywork is provided with a front apron and with a ride level
adjustment device which causes the car body to be lifted up in
order, for example to protect the front apron against damage in the
event of raised areas of the ground. For this purpose, in this
known prior art an obstacle sensor device is arranged in the front
region of the motor vehicle, and when the motor vehicle approaches
an obstacle the obstacle sensor device outputs a corresponding
obstacle sensor signal which is passed onto the ride level control
device. The ride level control device actuates a ride level
adjuster and the vehicle bodywork is raised automatically to a
relatively high ride level compared to a currently set ride level.
In this context it is also known to activate the ride level control
device manually and/or in an automated fashion as a function of
driving parameters by a control algorithm.
SUMMARY OF THE INVENTION
[0004] It is accordingly an object of the invention to provide a
motor vehicle with a ride level control device which overcomes the
above-mentioned disadvantages of the prior art devices of this
general type, which improves the actuation in order to change or
adapt the ride level of the motor vehicle.
[0005] With the foregoing and other objects in view there is
provided, in accordance with the invention a motor vehicle. The
motor vehicle contains an ignition, sensors, and a ride level
control device having a pneumatic lift system and a ride level
control unit to which operating parameters of the motor vehicle
detected by the sensors are fed. The ride level control unit being
active if the ignition of the motor vehicle is switched on. When
various conditions are met, the ride level control unit outputs a
signal to the lift system and lifting of the motor vehicle takes
place. A bidirectional connection between the ride level control
unit and the lift system is present and feedback from the lift
system to the ride level control unit takes place.
[0006] For example, a plurality of information items relating to
the current operating conditions for evaluation and adaptation of
the actuation are fed to the inventive system for actuating the
ride level of a vehicle. In this context, the various sensor
signals which are already available to the vehicle can
advantageously be passed on via a bus system to a ride level
control unit and evaluated there in accordance with predefined
algorithms. The ride level control unit correspondingly actuates a
pneumatic lift system which causes the vehicle to be raised and
lowered.
[0007] A further advantage is the provision of various locking
conditions in which the actuation of the lift system of the vehicle
is prohibited or interrupted. It has proven particularly
advantageous that the actuation of a lift system is permitted only
if the motor of the vehicle is running and a predefinable speed is
not exceeded. The pneumatic system is also configured in such a way
that the last position of the ride level actuation after the
machine has been switched off remains even without active
actuation. The system can thus store the last position and use this
position for the basis for further actuations when a restart
occurs.
[0008] A further advantage results from the fact that after
relatively long stationary times when a pressure loss has led to
lowering of the vehicle, a check is carried out after the engine
starts in order to determine whether the vehicle is in an
intermediate position. In this case, if there is sufficient
pressure in the pneumatic system the vehicle is raised
automatically.
[0009] A further advantage results from the monitoring of the
system to determine whether, after the starting of the system, the
setpoint pressure is built up in the system within a predefinable
maximum actuation time. If this is not the case, no further
actuation occurs and a fault in the system is completed and a
warning message is output. In this case, it is advantageously
possible to switch over to an emergency running function.
[0010] A further advantage emerges from the coupling of the system
to an automatic beam width adjustment. It is therefore possible to
ensure that the oncoming traffic is not dazzled after the raising
of the vehicle on the front axle.
[0011] Other features which are considered as characteristic for
the invention are set forth in the appended claims.
[0012] Although the invention is illustrated and described herein
as embodied in a motor vehicle with a ride level control device, it
is nevertheless not intended to be limited to the details shown,
since various modifications and structural changes may be made
therein without departing from the spirit of the invention and
within the scope and range of equivalents of the claims.
[0013] The construction and method of operation of the invention,
however, together with additional objects and advantages thereof
will be best understood from the following description of specific
embodiments when read in connection with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWING
[0014] The single figure of the drawing is a block diagram of a
basic configuration of an arrangement for controlling a ride level
in a motor vehicle according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Referring now to the figure of the drawing in detail, there
is shown a basic configuration of an arrangement for adjusting a
ride level of a vehicle. A central unit is the ride level control
unit which is donated by the reference symbol 10.
[0016] The ride level control unit 10 actuates the valves (not
illustrated in the drawing) and a compressor 20 of a pneumatic lift
system 11. In this context, signals 12 of the ride level control
unit 10 are passed on together with signals 19 of an engine control
unit 30 in an AND logic element 21 to the lift system 11. The lift
system 11 is in turn connected via a feedback line 13 to the ride
level control unit 10 and provides the ride level control unit 10
with feedback as to whether the final position for the raised state
or the lowered state is reached after a corresponding control
signal. At the same time, the driver is provided with information
via a display 14 which is connected to the ride level control unit
10 via a connection 15. The display 14 may be here an LED or
corresponding lettering in the combination instrument.
[0017] The ride level control unit 10 receives a plurality of
signals S1 to Sn, which are represented by the reference sign 16 in
the figure. These signals S1 to Sn may be, for example, a system
temperature, a position of the motor vehicle doors, positions of
further adjustment elements such as a soft top, a rear spoiler
and/or front spoiler.
[0018] Furthermore, the signal of an ignition 17 and a speed signal
18 are fed to the ride level control unit 10. The signal from the
ignition 17 and speed signal 18 are also evaluated in the engine
control unit 30, and a signal 19 is output by the engine control
unit 20 only when the ignition of the engine is switched on and the
speed is below a predefinable value. This ensures that the signal
12 which is output by the ride level control device 10 is output to
the lift system 11 for actuation only when both conditions (engine
running, speed below the reference value) are met.
[0019] All the necessary and available signals are therefore
detected and processed in accordance with the predefined
conditions.
[0020] A further signal, which is fed to the ride level control
unit 10 from the lift system 12 via the connection 13, is
information about the pressure in the lift system 11. The system
pressure is detected by a non-illustrated pressure switch and the
lift function is deactivated below a predefinable first pressure
value. In return, the system is not enabled again until the system
pressure reaches a predefinable second pressure value, wherein the
second pressure value is higher than the first pressure value, as a
result of which a hysteresis is implemented. In order to adapt the
system pressure, a compressor 20 is provided in the lift system 11.
The compressor 20 is switched on when the system pressure drops
below the first pressure value, and is switched off when the second
predefinable pressure value is reached.
[0021] A thermal protector is defined in the ride level control
unit 10 so that the temperature is evaluated for the actuation of
the thermal protector.
[0022] After the ignition has been switched off, the last position
of the lift system 11 is maintained. Therefore if the motor was
raised, it is still in the raised position when restarting
occurs.
[0023] If the motor vehicle is in an intermediate position after
the starting of the engine, the vehicle is raised provided there is
sufficient pressure in the pneumatic lift system 11. In this case,
the ride level control unit 10 automatically activates the raising
process.
[0024] However, if there is no system pressure present after the
starting process, the motor vehicle remains in the instantaneous
intermediate position. In the further course, the system pressure
is monitored after the engine starts to determine whether it
reaches the setpoint pressure within a predefinable time. If this
is the case, the raising function is automatically carried out. If
no sufficient system pressure was able to be built up within the
predefinable time, the intermediate position is maintained. If the
vehicle is in a lowered position after the starting of the engine,
no activation by the ride level control unit 10 takes place.
[0025] For actuation in the driving mode of the vehicle, the speed
v is monitored and as soon as a speed limit v (limit) is exceeded,
the vehicle is moved into a lowered position.
[0026] The lift system 11 provided according to the invention is a
pneumatic system which contains the compressor 20. As has already
been specified above, information about the lift system 11
indicating whether sufficient pressure is present in the lift
system 11 is also made available to the ride level control unit 10.
If this is not the case, the compressor 20 is actuated. Further
conditions have to be met for the actuation of the compressor. For
example, the engine must be running, the signal of the pressure
switch indicates a value which is lower than a lower limiting
value, the vehicle must not be in an active lowered position, and
the thermal protection is not activated. After an upper limiting
value has been reached, the compressor 20 is switched off
again.
[0027] When a defined thermal protection responds, the raising of
the vehicle is aborted after a predefinable waiting time of, for
example, 10 seconds, if the selected raised position has not been
reached.
[0028] Furthermore, a predefinable limiting speed is defined and
when this predefinable limiting speed is exceeded when the vehicle
is not in the lowered position, then one warning message is output
to the driver via the combination instrument.
[0029] With the present system it is also possible to carry out
leak detection. If, for example, the setpoint pressure is not
reached within a maximum actuation time of the compressor in a
pneumatic system, no renewed actuation of the compressor 20 is
carried out during this driving cycle and it is concluded that a
leak is present. A warning message is issued in the system.
[0030] A fault in the system is also presumed if both end positions
are detected as being activated at the same time if relevant
information is not available via the bus system or if the system
pressure is not reached after a maximum actuation time of the
compressor. In order to avoid inadvertent warning messages, the
pressure switch for the lower end position is debounced to the time
of, for example, two seconds. Pressure peaks, which occur as a
result of movements of the vehicle body in the driving mode, can
therefore also be equalized.
[0031] If such a system failure occurs, the lift function is not
available during the current driving cycle and an emergency running
function is generated.
[0032] In addition to the automatic actuation of the lift system,
manual control may also be provided, and may be carried out, for
example, by a push button key which can be operated by the driver.
The push button key is operated, for example, in jog mode. This
means that the vehicle is raised or lowered automatically until the
respective end position is reached after the push button key has
been depressed once. In order to avoid unnecessary upward and
downward movements of the vehicle, a protection function is
integrated. This provides for the manual raising to be limited to a
defined number, for example to six actuations within a predefinable
time period. If this number is exceeded, a corresponding protection
function is triggered and the manual actuation of the ride level
control unit remains locked for a predefinable time. This may be
signaled to the driver in the combination instrument.
[0033] Finally, it is also to be noted that the raising and
lowering of the vehicle influences the beam width of the
headlights. In order to avoid dazzling of the oncoming traffic, a
beam width adjuster LWR is indicated by the reference symbol 22 in
the figure. The beam width adjuster LWR is coupled, inter alia, to
the ride level control unit and ensures that the headlights are
correspondingly lowered when the vehicle is raised.
* * * * *